biegh



G. B. BIRCH.

COLLAPSBLE MANDREL APPLlcAloN FILED omzzo, 1911.

Patnted Sem. 2, 11119.. 1

NIH/EN T01? 11. Ul... Ital H IIIIIH H HHIIIIIII Nr ITBD sTATEs PATENT OFFICE.

oos'rar Binenn BIRCH, or BROOKLYN, NEW YoninnssiGNon To `initiation MACHINE COMPANY, or BROOKLYN, New Yoan, A cOaroBATION orNnw YORK.

coLLArsIBLE iviaNDnnL."

speciaeation of Letterari-nent.

Application filed October 20, 1917. Serialilo. 197,591.

, To a-ZZ whom t may concern:

- drels, of which the Be it known that l, GUs'rAr-B. Bison, a

citizen of the United States, anda resident of the borough of Brooklyn, in the city of New York, county of Kings, `and. State-,of

New York, have invented certainnew and useful Improvements in `Collapsible Manthe art of collapsible mandrels, it isa general custom to effectthe expansion and collapsin `of the mandrel bykmeans of lengthwise isplacement `of theouter ,and inner members constituting it; andthis is most usually effected by means of cam surfaces of somewhat complicated character. The ref sult of such construction is thatit is diliicult to produce collapsible mandrels of small diameter becauseY of the `amount of space 2 required by the expandingand collapsing elements; `and valso in making mandrels ofy large diameter, diiiculty is encountered because of the necessity of making the core disproportionate in size tolthe size of the mandrel as a whole in order to afford spa-ce i within a given diameter `for the collapsing and expanding elements..`

The main feature of the invention resides in a collapsible mandrel comprising a core and a shell of resilient sheet material slitted longitudinally into segments that collapse and expand uniformly lat oppositeeiids of y the mandrel.

Specifically, the shell of sheet 'materialv that surrounds the core is composed of inte gral segments partially separated by longi` tudinal slits, each slit running clear from one end of the shell and `terminating short of the other end, the adjacent slits extending from opposite ends of the shell. The result is a shellof sheetmaterial that is divided" into circumferential adjacent segments by means of longitudinal slits, eachsegment being connected at opposite ends to the next following is `a. specifiadjacent segment by an integral portion. .The integral portions of eachsection extend in opposite directions circumferentially at opposite ends. y

Other features of construction will appear as the specification poceeds.

In the accompanying drawings:

Figure l is whatmay be called a top plan view, partlybroken away, in` section of a collapsible mandrel embodying the inven tion. Fig. 2 is a vertical sectional view Onthe line 2-2 of Fig. 5. y Fig. 3 is a vertical sectional view on the line 3-3of Fig. 5.

Fig.` 4 is a vertical sectional View On" the une ef rig. 5.

Patented sept. e, i919.

' Fig. 5 is whatmay be calleda `side elevai "tionof the "mandrel partly in section and broken away,` showingthe shell in its eX- panded position. f ,y j

Fig. 6 is a view similar to Fig. 5 showing the .mandrel"- collapsed.`

Fig.` Z is a view, partly in elevation and partlyin section,.of a modified form of the. invent1on.` f

Fig; 8 is a line'8.-8 of Fig. 7.

Fig. `9 is a ldiagrammatic view showing a lliellkthat has been cut and laid `out as a fiat` `l indicates a core of any suitable construction `and is `here shownas a simple bar or" shaft. `2 is the outer shell composed of a plurality of segments that are formed by means Oflongitudinal slits 3, each slit running `clear from one end of the shell and terminating short of the other end, the adjacent slits extending from opposite ends of the shell. This will be apparent from the diagram of Fig. 9 in which the Oppo-sitely disposed slitsare clearly shown. The result is that the segment 4 is connected at its Opposite-ends to the next adjacent segment by an integral portion 5, said integral portion ex-` tending in opposite directions circumferentially at opposite ends as shown.

ln Figs. l to 6 inclusive there are but two segments while in Figs.` 7 and 8 there are four se ents.

verticalsectional view on the present instance taking the form of pro- 'ections 6 `preferably having cam surfaces carried by the core, there being, preferlso ably, a plurality ofsuch members in alinement with each other as shown more particularly in Fig. 1.` In line with these projectionsk are perforations or openings 8 in the shell. 9 indicates a member on the core that extends into the closed slot 10 of the shell to preserve the members 6 in alinement with openings 8. It will be apparent that, if the core. and shell are displaced longitudinally With respect to each other, and suiiiciently to bring the projection 6 into `the plane of the openings 8, the resilience of the material of the shell Will cause said shell ,to collapse in the manner indicated in Fig. 6; and that the collapsing action of the shell will be substantially uniform at opposite ends thereof because of the oppos'iitely disposed slits. Also, When the core and shell are displaced longitudin-ally with respect to each other in the opposite direction, the cam surfaces 7 of the member 6 will cause the shell to expand as these surfaces bear against the inside of the shell in the manner indicated in Fig. 5. l.The amplitude of slot 10 is suchk that the member 9 will remain in the plane thereof .Whether or not the mandrel is in its eX- panded or collapsed 'position so thatt thel parts 6 and 8 will be maintained in alinement With each other. It Will be understood that the extent of the projection of the member 6 outside the core 1 shouldk prefer-4Y ably not be greater than the thickness of the shell so that when the parts are in their collapsed positions, as in F-ig. 6, said member 6 will not project beyond the uniform circumference alforded by the shell. The pin 9l is located outside of that part of the vmandrel on Which thel reWound coils are the segments when reWinding material on the mandrel, suitable means are employed that, in this instance, take the form of projections 11 carried by the shell and sliding in en agement With grooves 12 of the core. It Wi l be understood that this construction may be applied either to the form shown in Fig. 1 or to the form shown in Fig. 7. It will also be understood that when these means are employed, the members such as 9 and 10 may be omitted, if desired, since members 1l and 12- Will maintain proper alineinent ofthe parts.

I claim:

1. A collapsible mandrel comprising: a core, a shell of sheet material surrounding the core composed of integral segments partially separated by longitudinal slits, each slit running clear from one end of the shell and terminating short of the other end and adjacent slits extending from opposite ends ofthe shell, means for ex anding and collapsing the shell by a re ative lengthwise movement of ,the core and shell -including projections on the core and openings in the shell, and means for maintaining the co operating expanding means in alinement With each other.

2. A collapsible mandrel comprising: a core, a shell of sheet metal surrounding the core composed of integral segments parv tially' separated bylongitudinal slits, each slit running clear from one end of the shell and terminating short of the other end and adjacent slits extending'from opposite ends of the shell, means for expanding and collapsing the Ishell by a relative lengthwise movement of the core and shell including projections on the core of a height substantially equal t0 the thickness of the shell and openings in the shell, and means for maintaining the coperating expanding means in alinement with each other.

Signed at Brooklyn, in the county of Kings and State of New York, this 11 day of October, 1917.

GUSTAF BIRGER BIRCH. 

